By Lieutenant Commander Oliver-Leighton Barrett, United States Navy (Ret)Senior Research Fellow, the Center for Climate and Security

In restaurants across South America’s largest and most populous city, Sao Paulo, customers are being served drinks and meals on plastic cups and plates. The reason? A severe shortage of clean water, exacerbated by drought, means there’s no water for washing dishes. A burgeoning urban population and the effects of climate change are likely to exacerbate Brazil’s water woes. And given Brazil’s evolving role on the international stage, as an agricultural giant and a standard-bearer for a group of emerging economies, this will have both domestic and international security implications.